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Contents
…Non-precision Approaches; ...Approach Minimums for Non-Precision; …Complex Approach Minimums; ...Stepping Up to the Step-Down Approach; ...Lesson; …The Best of a Bad Approach; ...IFR Go-Arounds; ...Go-Around Essentials; …Straight-in Approach; …Localizer Approaches; …Checking Localizer; …VOR Approaches; VOR Minimums; ...Off Airport Facilities; ...On Airport Navaids; …Intercepting a Radial; …VOR Checks; …ADF Features; …Non Directional Beacon Approach; ...NDB Flying; ...Standard Outbound Tracking; ...Intercepting a Bearing; …ADF Orientation; …Simple NDB approach; …Final approach Tracking; …NDB Cold approach;… If You're Fussy; …GPS; …GPS Approaches; …GPS Instruction; …GPS in an Emergency; ...GPS as an Emergency Wing Leveler; …GPS as a Substitude; …Emergency ADF use; …Visual Procedures; …Visual approach; …Contact Approach; ...ATC and Visual Approaches; …Types of Vectors; ...Pilot Responsibiity Using Vectors; ...ATC Responsibility Giving Vectors; …Approach by Vectors; …Charted Flight Visual Procedures (CFVP); ...Pilot Responsibilities; …PAR (GCA)Approach; …Been There; Done That; …Airport Surveillance Radar Approach (ASR); …No-Gyro Approach; …Visual Descent Points

Non-precision Approaches
VOR--NDB--GPS--LOC--ASR--LDA--SDF approaches do not have vertical reference other than the altimeter and the direction of the approach may not be aligned with the runway. You will be expected to maneuver for the landing. The minimum descent altitude (MDA) may be very near the low IFR altitude of weather. The MDA may be relatively high depending on distance, terrain, and type of approach. You cannot leave the MDA without seeing the runway.
Just seeing the ground is NOT enough.

The design limits of the system set the minimums. The approach is named by the navaid and runway at the airport. The navaid may be before, beside, on, or beyond the airports. A margin of error is built into the plate by TERPS (rules for making approaches) but the expectation is that the pilot will fly the procedure perfectly so as to maintain these safety margins. The non-precision approach usually does not parallel the runway centerline; instead the electronic line takes us to the end of the runway at an angle. There is no electronic vertical guidance. A turning maneuver is going to be required for landing. The MDA will vary with the terrain, lighting available and system used

A pilot has a choice of doing the approach with vectors or as 'own-nav'. Vectors are easier since ATC usually sets you up with a 30-degree intercept to your inbound course. Your 'own-nav' may require that you reverse your direction of arrival. This means using a procedure turn or a holding pattern to make the turn-around, and begin your descent when established. There are required reports at the fix inbound and when established from the procedure turn.

The chart will have course, altitudes, frequencies and times for you to utilize during the approach. The approach is segmented into three parts:
1. Initial segment gets you lined up for the approach.
2. Intermediate segment usually begins the descent.
3. Final segment gives you a timing point, minimum descent(s), and missed approach point.
4. Missed segment which begins at the missed approach point with a direction, and climb required.

A non-precision approach has four segments; each segment begins at a defined point. The initial approach segments begins at the IAF. At the intermediate approach segment you are established on course and descending. The final approach segment usually has a FAF but not always from which time or DME is used to guide the descent to the MDA. You do not leave the MDA until seeing the runway. The fourth segment is from the missed approach to the missed approach fix. The route and altitudes for each segment are shown in plan and profile views. By flying the published headings and altitudes you are protected from obstacles.

Being "Cleared for the Approach" by ATC means that you can follow the published procedure.
By following the publish routes at the published altitudes you are 'guaranteed' not to hit any ground object. That is, providing you have correctly set your altimeter. Historically the 'chop and drop' has been the accepted procedure and could be used in familiar situations. Otherwise, the stabilized approach using the airspeed, time, and descent rate is to be preferred. Descent from the FAF to the MDA have traditionally been of the 'chop and drop' type but today the use of DME makes stabilized descents more common. The VDP (visual descent point) either created or charted makes it possible for the pilot to prepare for a landing for straight in approaches.

The purpose of the non precision approach is not to put you on the runway. Its purpose is to get you down out of the clouds and in sight of the runway. The pilot is expected to navigate to the missed approach point. Only if clear of the clouds will he will be allowed to maneuver visually to the runway. MDA are usually below standard pattern altitudes and will require a higher level of maneuvering skill. Practice your short approaches in better conditions.

If you descend to the MDA and see the runway but not in time to make a normal landing, you must climb to circling minimums before turning. In the turns you are required to keep the airport in sight at all times. You do not descend below circling minimums again until lined up with the visible runway. Non-precision approaches at night should only be flown if there is a VASI. If at first you do not succeed…quit and go to a better place. Most approach accidents occur during the second attempt.

You can use or make a visual descent point (VDP) as a landing aid. TERPs require a VDP for all straight-in non-precision approaches except for procedures with remote altimeter setting, where the descent path is below a required step-down altitude and where it would be between the MAP and runway. No VDP will exist where an obstacle exists. The absence of a VDP serves as an obstacle alert.

The VOR and NDB approaches do not have the options of precision approaches. Only Minimum Decent Altitudes exist. The circle to land minimums have Height Above Airport numbers parenthetically rather than runway numbers. The circle to land altitude and distance is determined by aircraft category speed. For straight-in minimums there are three requirements:
1. Approach aligned within 30-degrees
2. Approach must cross the runway threshold
3. Descent gradient cannot exceed 400 feet per nautical mile.

Non-precision approaches, while less accurate, are easier to fly because the altitudes are mostly level flight with only one needle to follow. On reaching the minimum descent altitude you should have established a personal visual descent point from which a normal straight-in landing can be accomplished. Other wise do not descend below the circling minimums.

Localizer types of non-precision approaches are the localizer, LDA and SDA. Other non precision approaches are the VOR, and the Airport surveillance radar approach (ASR). ASR approaches require a published plate. A given approach may be entered as (1)a straight in approach or (2) as a full approach.

--Once on the approach use power for descent, level and climb
--Work load must not interfere with control.
--Focus only on the turn when turning.
--Consider downwind landing instead of circling.
--Make small power changes even to climb.
--Never bust minimum altitudes.

Descent from the FAF to the MDA have traditionally been of the 'chop and drop' type but today the use of DME makes stabilized descents more common. The VDP (visual descent point) either created or charted makes it possible for the pilot to prepare for a landing for straight in approaches.

Approach minimums for non-precision
--Straight in minimums are visibility only.
` --Circling minimums require a ceiling.
--Get down to the MDA well before the airport.
--You win by being allowed to make a scud run to the airport.
--Nonprecison approaches should be flown precisely.
--Level off at the MDA and let person not flying look for airport.

Complex Approach Minimums
Lowest minimums only if:
1. Local altimeter setting
2. Identify 2.5 DME fix
3. Straight in landing

Stepping up to the step-down approach
The step-down is used to give the non-precision approach lower minimum descent altitudes. The basic non-precision without the step down takes you to the MDA right after the FAF. The step-down requires that you make one or more altitude stops before reaching the MDA. The steps are based upon aircraft category and the altitudes are critical with minimal obstacle clearances.

There are two methods of doing the approach. One is to follow the published procedure and chop-and- drop between each step while maintaining a constant ground speed in the drop and level flight. The other option is to calculate the rate of descent for the entire procedure and initiate that rate of descent at a constant ground speed throughout. The latter procedure will allow you to cross each fix at the proper altitude in a stabilized airspeed approach.

Lesson:
In level flight establish aircraft in your approach configuration. Note (record) for memorization the configuration settings of gear, flaps, and power for level flight. Index these settings as what you will use for each time you level off. If you are not loaded according to your standard practice, you should give your descent and level off procedure a trial run before making the approach.

The step-down descent requires superior aircraft control. Descent is commenced first with carburetor heat and a power reduction, rudder, and then elevator. Touches of rudder are best with power changes, left for reductions and right for increases.

The 3 to 1 descent glide plane can be determined quickly by dividing the altitude to be lost by three and using the dividend to give you the miles required to make the descent. A 3 to 1 descent will require 6 miles to descend 1800’, 5 miles for 1500’ and so on. To find the required vertical speed for the 3 to 1 profile multiply your ground speed by five and add 50. Ground speed of 90 x 5 = 450 + 50 = 500 or 500 feet per minute descent will keep you on the descent profile. at 120 knots you will need 650 fpm descent. Descents over 500 fpm are uncomfortable for passengers.

Title of a step-down approach reveals the approach gradient. A letter instead of a runway number tells you that the descent requires more than 400 fpm descent. This also tells you that only circling minimums apply. A straight-in can be made if conditions allow a normal approach and landing. The step fixes will be on the GPS data base if they have a five letter identifier. Fixes shown by triangles are not in the database and are titled as a CF (centerline fix) for a runway number.

With consummate skill, a pilot could determine both the speed and descent rate required to make a constant descent from fix to fix to fix. Never dive for the MDA. You may need to descend in excess of the slope that gets you to the MDA at the exact time for the missed. Otherwise, you can have no expectation of making a normal approach to landing. This eliminates leveling off and you should reach a visual descent point and MDA at the same time. Not easy but certainly something to strive for. A MAP at the threshold of a mile long runway and a MDA below 400’ AGL will put you at the far end of the runway unless your slope exceeds the 3 to l norm.

The Best of a Bad Approach
Preparation can improve the precision of a non-precision approach.

Letter designators such as VOR-A or NDB-B or if the descent angle is steeper than normal are indicative that only a circling approach is authorized. If making a non-precision approach that has a steep approach angle you had best configure the flaps to get the desired rate of descent. Any descent rate over 700 fpm is not in the normal range.

Clearance for the approach should include distance to FAF and allow you to descend to intermediate segment altitude. If you feel that you are being vectored in at too high an altitude or too close word your request according to your needs. Watch out for dumb mistakes. Use the checklist. Don't descend until you know where you are. Know the visual descent point and pre-plan one of your own. (Use the first two digits of the MDA as seconds subtracted from total approach time to set time reaching VDP for normal landing approach.)

Essential to any non precision approach is that the glide path be stabilized. A stabilized approach means that you have several constants established. Power is a constant. Trim is a constant. Airspeed is a constant. Altitude is a constant. These constants are maintained by constant reference to the instruments and a constant light touch on the controls. The pilot knows the power, attitude, trim, attitude and airspeed required for any pitch change to another. All changes are pre-planned and smoothly accomplished. This is practiced and perfected by practice and repetition in VFR conditions. Never fly an instrument procedure others than an ILS at night to an unfamiliar airport with an unfamiliar missed approach procedure.

IFR go-arounds
Take all the training you need to get rid of any inefficiency or poor techniques. Unless you have begun your landing descent at a valid visual descent point (VDP) with the required visual references you must make a go-around. Primary to any go-around is the immediate application of all available power. You do not have full power unless you take off carburetor heat. Do NOT look into the cockpit. Keep your eyes outside. Hold heading with rudder. Lock your elbow against the door and fly level holding heading. Lose altitude if you must, the aircraft will fly and accelerate better in ground effect. On reaching climb speed as determined by sound or a quick glance. Remove flaps only if necessary for climb. Initiate a climb.

If you do not have the runway at MDA/DH, you may not be where you should be. In this case you cannot afford to lose altitude. Leave the plane in a landing configuration if it is able to climb reasonably well. Practice making full ‘dirty’ go-arounds at altitude. Also practice getting a better climb after you are well into the go-around.

Don’t press a touchdown that is going to be long on a short runway. When there are strong cross winds expect to make your go-around early in the approach when your needles have trouble finding center.

Go-around essentials
Flight visibility is the governing factor in Part 91 instrument approaches. The reported ground visibility is a factor only in that
the FAA may call your 'flight visibility into question. One way to improve your preparation for the missed is to incorporate
your missed approach configuration of gear, flaps, and airspeed into your approach configuration.

The use of an autopilot-coupled approach presents a problem if the missed approach is not also coupled to the autopilot.
I have had pilots have real difficulty with the missed because of the transition from autopilot into a hand flown missed.

When things go wrong on an approach the best option, as in other landings, is to go-around as required by the missed
approach procedure. This is recognized as a very correct --command decision. The decision is followed by the number
one priority of flying the airplane. You do this by applying full power, cleaning up the configuration at a climb attitude.

The decision altitude or minimum descent altitude is the height above touchdown elevation and not the runway threshold.
The importance of flying a clean approach is that you will be executing the missed approach in protected airspace. The
accident record of missed approaches is that only about five related fatal accidents occur per year. Considering all the
missed approaches made this is a very good record.

You are in protected airspace that extends for 15 miles with a 40' to 1' terrain clearance plane, which requires a climb rate
of 253 fpm. Do not make any turns until reaching the specified plate altitude. Turning too soon can be just as fatal as
turning too late. Breaking off an approach requires that you climb straight to the missed approach and follow the published
turn procedure.

If you are flying the circle to land approach, the missed approach procedure requires that you circle back to the runway
with the missed approach procedure. You are not obligated to then fly to your alternate. The purpose of the alternate is
to advise ATC what to expect if radio failure should occur.

Don't try to hard to succeed on an approach. Pushing your luck and skill is the road to failure. Making the missed approach
means that weather was below minimums, not that you were a failure as an instrument pilot.

Failure to initiate the approach in a timely manner statistically kills far more pilots than does the missed. The worst killer is
the second approach made because the pilot saw the runway in passing.

--Don’t second guess the go-around. Do it!
--Use full power
--Hold heading and altitude until reaching climb speed and afterwards.
--Climb with flaps if you can.
--Clean up plane.

Straight-in Approach
The tower is not responsible for any traffic separation until that traffic is on the ground but arriving traffic must be far enough out to allow surface traffic to clear the runway before touchdown. There is no ATC separation by the tower while you are in the air even though you may be talking to the tower. There is a hazard associated with the straight-in approach. Aircraft viewed directly from the rear are difficult to see since there is no relative motion. Motion is the first thing the eye sees. An airplane both in front of you and lower is even more difficult to detect. Use the radio.

The straight in approach is so called because it does not use a course reversal to become established on final course. Radar vectors can be used to bring you so as to intercept the final approach course. A no procedure turn (NoPT) transition is possible when the feeder route has both direction and altitude for an easy intercept and descent. An approved transition must have a minimum altitude, distance and heading. Approaching from a hold is allowed when the inbound leg is aligned with the final approach course. May be prohibited by note. The DME arc is a curve route to intercept the final approach course. NoPT is required but DME is.

Straight-in minimums are not published or available when the final approach course is not within 30 degrees of the runway centerline OR a normal rate of descent cannot be used from the MDA to the runway. When the approach plate has a number as part of its title then the runway is within 30 degrees and the straight-in is authorized and the minimums are published. Any time you fly such an approach with a crosswind component corrected by your heading, the airport will not be over the nose of the airplane.

At many airports the approach to the runway on the chart may require either a downwind landing or a circling approach. Lower minimums will apply to the downwind landing. You will need to adjust your airspeed to get the desired ground speed caused by the tailwind. If the tailwind is only 10 kts it will double your landing distance.

Localizer Approaches
--6 degree course accuracy to threshold.
--OBS should be set to approach course as a reference heading only.(disconnected).
--Backcourse ILS is non precision localizer approach.
--Localizer directional approach (LDA) flies like a localizer approach but can bring you in to runway from 30 degree angle.
--Some LDAs have glide slope.
--Simplified directional facility (SDF) approaches uses poor quality antenna with course width of 6 to 12 degrees.
--Use approach chart to obtain reference descent rate in fpm.
--Bracket this rate to get and keep correct slope
--Your primary pitch instrument for straight and level at the MDA is the altimeter (the one with the numbers).
--A clearance to the ILS approach is likewise a clearance for the localizer but with higher minimums.
--An ILS/localizer approach has two FAF's only one of which is timed. The interception point of altitude with glide slope
is the FAF for the ILS.
--You cannot fly the Localizer if you have flown the ILS to below the MDA for the localizer.
--The LOC (localizer) only and VOR approaches look pretty much the same as an ILS except that they don't have the "go up/go down" glideslope needle, just a "go right/go left" needle.
-- The VOR and localizer are on independent circuits. They require independent checkout.

Checking Localizer
A localizer can be checked for accuracy by departing a runway served by that localizer. Tune to LOC frequency while taxiing and note CDI movement as you move on to runway. CDI should center as you line up on runway centerline. This will not work at CCR 19R except at the very end of the runway due to offset.

VOR Approaches
Item: VORs with HIWAS do not have two-way communications.
Accuracy
--91.25 Requires 30 day check of VOR accuracy before IFR use.
--Use of VOT give zero From or 180 degrees To with allowable error + 4 degrees.
--Ground checkpoints in AF/D +4 degrees
--Airborne checkpoints in AF/D +6 degrees
--Dual VOR check within 4 degrees
--VOR idents in a series of four followed by DME ident.
--VOR deflection is 10-degrees from center to side
--Any time dual VORs have a common problem it is probably the shared antenna

On a VOR approach, the VOR can be located at:
--Airport
--Missed approach point
--Initial approach fix
--Final approach fix or
--Miles from the airport.

VOR Minimums
Fewer options for the VOR and NDB than for the ILS. Some non-precision approaches lower the minimums when light
systems exist. The MDA boxes do not include DA(H). Circle to land minimums are based on HAA elevation as shown
on the right side of the chart. Numbers in parentheses are Heights Above airport (HAA). Radius of the circle for category
A aircraft is 1.3 nm. The speed you fly determines the aircraft category. If there is no speed/time chart then timing is not
authorized.

Straight-in-minimums require three things:
1. Runway alignment within 30-degrees
2. Approach must cross threshold
3. Descent to be less than 3.77 degrees or 400' pnm.

 Off Airport Facility
The course is aimed at the airport reference point.

On Airport Navaid
The final course is aimed at the navaid but will intercept the runway centerline optimally at 3000' from threshold for circling. Straight-in is aimed at the threshold.

VOR is four times laterally less accurate than an ILS localizer. This means that every 1 degree of a VOR has a built in it an error. The error is easily computed by taking the distance from the VOR in nautical miles and adding two zeros.

Consider that a VOR is allowed up to six degrees of error (airborne) to either side of a course line. Take a VOR distance such as CCR at 3.1 miles from the airport. This is about 300' error per degree. A full 6 degree error would amount to missing the end of the runway by 1800'. This does not include possible pilot error such as a 1-2 degree error in setting the OBS.

Pilots should never fly anything other than the course radial on the OBS. You should look to left and right of your course for the airport. How far to each side you look would depend on the distance between the airport and the VOR. You never track an incorrect radial in anticipation of possible equipment error. Use Airman's A/F Directory to determine useable directions and altitudes of all navaids. CCR VOR can fly you into Mt. Diablo from the southeast.

Suggestion: Use ADF "0" position to set altitudes assigned by ATC.

Intercepting a Radial
--Along an airway a 45 degree intercept
--On approach use 30 degrees
--10 degrees maximum on the ILS and use rudder for 5 degree corrections

In some instances a greater than 30-degree arrival may not require a hold. The FAA may design an approach where the hold is so removed from the final approach fix (5 nm) that sufficient time for course alignment exists.

VOR Checks
There are 6 ways a VOR can be pilot checked for errors:
--VOT
--Ground check point
--Dual VOR check
--Radio shop check
--Designated airborne check
--Homemade" check

Every VOR has a dedicated monitoring system where other navaids may or may not be monitored. Monitors check the signal and any required accuracy on a status panel with alarms and lights. Unmonitored navaids cannot be used to meet alternate requirements of IFR flight and are noted in the A/FD either with and N/A on an approach plate or with a ‘tower closed’ note. The pilot who is using an unmonitored navaid for an actual approach had better maintain a constant listening watch on the frequency and flags.

ADF Features
The NDB approach is designed to have protected minimum obstacle clearance is 300 feet vertical and 1.25 miles wide at the facility. A formula is used to determine the protected space as the missed approach point which amounts to 6000' wide per mile. You have 30 degrees angular space, 15 degrees to each side, to miss the runway and still have protected airspace. The PTS standards allow only 10 degrees bearing error to the approach course.

Low frequency radio 200-1600 KHz with both loop and sense antennas. Not limited to line-of-sight but by power. HH power good for 200 miles down to compass locator or locator outer marker (LOM)at 15 miles.

The ADF course is the intended magnetic flight direction. When ATC directs you to fly with reference to an NDB they will always give a bearing from or to the station. The to or from may be either way by ATC while meaning the same thing. If you are in doubt as to ATC intentions reverse the term and direction used by ATC and ask for confirmation.

I usually teach the NDB/ADF procedure with the azimuth card fixed at "0". Using this method the magnetic bearing can be read by mentally superimposing the ADF needle on to the heading indicator. The FAA written test uses problems that require use of the formula MB=RB+MHs. This means that to find the magnetic direction to the NDB to add the relative bearing to your magnetic heading. The math involved in this procedure when flying can be avoided by rotating the azimuth card. ADF needles always move into the wind. When holding an approach heading the needle will point toward the course line.

Rotating the azimuth card makes the ADF into a pseudo Radio Magnetic Indicator (RMI) without the remote compass. In the RMI the azimuth card rotates automatically. With the ADF you must set the card to the desired magnetic heading. The heading selected in the course line + the predicted wind angle. You are trying to get the tail of the needle to indicate the approach course line. When the tail of the needle indicates to the right of the course line you will turn to the right for about 30 seconds before returning to the WCA heading. Works the same if the tail moves to the left. Once you have turned the card it is best to leave it alone unless you have grossly misjudged the WCA.

Items:
---When NDB is used to form airway the magnetic bearing from the NDB is used to form the radial.
--An unused ADF is likely to get needle problems
--Not all ADFs use two antennae.
--Check an ADF malfunction by going to ANT mode (Some needles will 'stow' at 90 degrees.)

Non Directional Beacon Approach
The secret to flying the off airport NDB approaches is: after station passage turn to the final approach course and maintain that course for at least 30 seconds, despite what the needle is telling you. Keeping this lesson in mind should make flying NDB approaches much simpler in the future. The NDB approach is generally considered one of the tougher items on the flight test for the instrument rating. If you asked a bunch of instrument-rated pilots to list their favorite approach equipment, you'd probably get a list something like this: #1 ILS. #2 LOC only (no glideslope), #3 VOR, and #4 NDB

NDB Flying
--Set HI with compass
--Turn to fly direct to NDB
--Fly until needle is off the heading. Its deflection is the wind direction.
--Turn to the needle twice the displacement.
--When needle deflects by the original deflection amount, take out half the correction and see if needle stabilizes as a indication of correct drift correction.
--Repeat the process as distance permits.
--On station passage turn to inbound course with wind correction applied.

Standard Outbound Tracking
--Initially the needle is at 180
--Hold the course but any needle movement indicates direction of the wind.
--When needle is displaces 5 degrees, make 20 degree turn toward needle.
--When needle tracks 20 degrees take out 10 degrees.
--You will know you are tracking correctly when needle deflection is constant.
--Repeat as necessary.

Intercepting a bearing:
--Turn to desired magnetic heading. Needle deflects to station.
--Turn toward needle double the deflection.
--Fly heading until needle deflects half of intercept angle.
--Turn to original desires heading. Needle should be centered.
--Repeat as required.

If you are constantly correcting you heading to fly to the NDB, this is an indication that you have not made a wind correction
and are flying an arc to the NDB. Without the wind correction information that should be determined inbound to the NDB,
you have only one option. Fly the charted bearing from the station. This is not the way it should be done but this method has
a good chance of keeping you within the allowable error range.

Another method… for flying from the NDB is…
--Fly the charted course until off 10 degrees.
--Turn 30 degrees toward the needle until needle is on course.
--Take another 30 degree cut until needle is on course.
Repeat (works in crosswinds)

ADF Orientation
--Set magnetic heading of aircraft to the top of the ADF card.
--Tail of needle gives bearing from station.
--The ADF can detect thunderstorms
--ADF needle is unreliable in a turn. Use timed turns for changes.
--Monitor frequency when sole source of navigation.
--Consider putting magnetic bearing to the station on top.
--Once established make only small heading changes.

Simple NDB Approach
The difference between the NDB and the others is that there isn't a single dial in your cockpit that you can refer to, to see your tracking error. You must combine the information presented by the HI and the ADF, if you wish to accurately track to or from an NDB

You can practice learning to track using the NDB. When flying cross-country, work on finding the proper crab angle. Good visualization practice. But during the approach, people under stress may misinterpret the dials and ‘correct the wrong way. Flying the NDB approach, which has an NDB located 4 miles west of the threshold of runway 09.

270 <----- /------- * -- 090 --> 9__________________|

/

045 / 225

When cleared for the NDB 09 approach, so you could simply "home" to the NDB, which is your IAF (Initial Approach Fix). ‘Homing’ with an ADF simply consists of keeping the needle on the ‘nose’ of the aircraft, or on the zero at the top of the ADF indicator. With a crosswind, our just flying the needle will get us there. Spend any excess time studying the plate.

Get the important items:
A pproach - the right plate?
M inimums - MSA, PT, FAF, MDA
O vershoot - quickly review which way, how high, how far
R adios - ADF tuned and identified. Radar, ATC, CTAF
T imes - get a time to the Missed Approach Point (MAP), VDP?
S peeds - groundspeed based on wind

Passing the NDB outbound, some type of procedure turn. Course reversal is easiest but always to the published turn side. Otherwise, visualize what the wind is doing to you on each straight leg of the procedure turn, and make a correction for it. A crosswind, crab into it. A headwind, increase your time significantly. A tailwind, decrease your time slightly. Headwinds hurt more than tailwinds.

Cockpit checks now. Check your Heading Indicator against the compass. You cannot fly an accurate NDB approach without an accurate heading reference.

Major NDB problem is lack of ident process. NDB navigation relies on the accuracy of the compass. Compass deviation must be applied to NDB bearings. Avoid flying an NDB using an outbound track from a distant station. Configure before beginning the approach. Don’t home, track to an NDB. This means apply a course correction that negates the wind effects. NDB station passage is noted when the needle is off the wingtip.

High powered AM stations can be good for 500 miles. The accuracy of the ADF is directly related to the accuracy of your compass and your HI setting. Compass corrections of the compass apply to the NDB. The recency of a compass card is important.

Flying an outbound NDB track from a distant beacon should be avoided. Before you start on approach you must be configured and on speed. Homing does not work inbound. Track to an NDB if you want to remain in protected airspace. You must track outbound from an NDB by getting on the outbound bearing and then correcting for any crosswind to remain on that track. This must be done before starting on the approach.

Final Approach Tracking.
Turn initially to a heading of 090 and begin descent started to get your altitude for the FAF (Final Approach Fix). This is usually lower than your procedure turn altitude. Be sure to keep a 500 fpm descent rate going, use 600 or 700 fpm if you have a tailwind.

If there's no wind, a heading of 090 will take us right to the NDB. Rather than using any tracking and correction technique just simply home to the NDB. Needle on the nose, back to the NDB. By homing to the NDB, we are assured of a station passage. On Passing the NDB (the FAF) inbound, turn back to 090 and start a descent, down to your MDA (Minimum Descent Altitude). Eessentially, after station passage just fly a heading of 090 until you see the runway, or your timer runs out at the MAP. At a ground speed of 90 knots, it will take 2 minutes to travel 3 nautical miles to a 1 mile final for runway 09, at which time you should be visual with the runway, and start your descent from the MDA.

But let's say we've got a 30 knot direct crosswind, which is a lot at 500 feet AGL. If we get a good station passage, and just ignore the wind by flying a heading of 090, after 2 minutes the crosswind will have pushed us 1 nm off course. Instead of being 1 mile from the runway threshold, we will be 1.4 miles, which is a pretty good return for such a simple procedure.

If you think about it carefully, it's actually going to be better than that. With a strong wind from the north, while homing to the NDB after the procedure turn for the FAF, let's say we eventually weathervaned to a heading of 070 at station passage. After we pass the station inbound, during our turn from 070 back to 090 we will travel somewhat north, or upwind of the desired track, so we probably won't drift a whole 1 nm downwind.

Also, if you have a higher groundspeed than 90K, you will be affected less by the crosswind. There's less time for the crosswind blow you off course after passing the FAF. The neat thing about the above NDB approach is that at no time did you ever have to track using the ADF. You always flew and maintained headings.

NDB Cold approach
The NDB is the easiest 'cold approach' to make.THE COLD APPROACH (no opportunity to use the 6 p's)
--Frequencies at top of chart Locate VOR's relative to approach
--Check/recheck OBS settings
--Write time and MDA/DH on hand

--The side of the published procedure turn is mandatory
--A published teardrop procedure is mandatory
--The completion distance from the fix is mandatory
--It is TOO LATE to study the plate inside the FAF
--Base all wind corrections on the point of the ADF needle.
--The arrowhead will point the direction the wind is going.

You should know that the NDB power and range are in the Airport/Facility Directory. The ADF needle always points to the station and the tail of the needle give the aircraft position. To get your magnetic bearing to an NDB you must use your imagination to put the ADF needle over the HI. Changing the ADF card makes the process more difficult, leave it on zero.

The curved path that occurs when flying to the NDB without any wind correction is called a loxodromic curve. Tune in the frequency and the needle will always point to the station. The needle that is not pointing to the station will either point to the left or right of the station. Make your correction for wind or course by correcting to the direction of the needle, left or right. In each case you must make a heading change that is greater than the needle deflection.

You should not try to track a course until you have intercepted the course. Once intercepted you must track with the understanding you will need to intercept again and again. This is especially true in NDB holding patterns.

If you’re fussy:
Slightly modify the above procedure. With a groundspeed of 90K, we know that two minutes after passing the FAF we should be visual with the runway, and in position to start descending on final. So, passing the NDB inbound, turn to a heading of 090 and hold it as accurately as you can for one minute. After one minute, observe the ADF indication. Let's say that it's now 190 relative. This means we have drifted south (to the right) 10 degrees during the one minute after we passed the FAF.

To correct for it, we turn left 20 degrees to a new heading of 070 for the remaining one minute. This 20 degree correction for a 10 degree drift is exactly the same track correction method you used as a student pilot on your private pilot flight test.

GPS
Newer is not always better. Within a mile at low altitudes the VOR is more accurate than unaugmented GPS. The GPS is always better than the NDB for accuracy. The two levels of GPS use are the Standard Position Service which is within 100 meters 95% of the time and within 300 meters 99.99% of the time. The second service is for the military only as precise positioning Service.

GPS Approaches
GPS will provide for non-precision operations into small airports. The presence of obstacles may not be depicted. GPS is not conducive to windshield scan. Best to have a third person aboard who is supposed to watch for other aircraft.

IFR has a higher level of skill requirement but the use of ATC services, especially radar, is a given so the process is simpler. If you plan to use a GPS approach at a given airport, your alternate must have an instrument approach procedure other than the GPS. IFR GPS must have FAA approved flight manual supplement and current database. Must query FSS for GPS NOTAMs. File as /G aircraft

GPS Instruction
Begin by running through the GPS approach set-ups. Do several without flying them. The set-up will be different full approaches, approaches with vectors and when an initial approach fix is used. Fly the approaches at 1,800’ AGL above
the published altitudes so you can observe the GPS perform sans altitude, climbs and descents. After such a dry run try
the full approach with missed included.

GPS/IFR requires five satellite signals. Reception depends on the satellite angle and any obstacle interference. The GPS
uses triangulation and ranging. IFR receivers have receiver autonomous integrity monitoring (RAIM) for checking the
integrity of the signals. Non-IFR needs only three satellites for a fix. The GPS receiver and the satellite match codes and clock times to determine four lines of position. This position can be by means of a waypoint names or by longitude and latitude.

GPS reception will soon be available through Local Area Augmentation for Category II and III with Category I to follow.

Both the GPS and the VOR navigation systems are tied to magnetic references. This is because the compass, the basic direction instrument, is magnetic. Just as runway numbers are changed over time, so are VOR based airways constantly requiring tweaking to correct for magnetic variation changes. Long GPS routes that follow VOR routes should have intermediate fixes to allow for variations between GPS and VOR magnetic difference.

GPS in an Emergency
You can use GPS to position yourself on short final to a runway under the worst conditions if you have practiced a
relatively simple procedure. There are several requirements.
--You must be able to fly timed distances on precise headings.
--You must have an aircraft that is willing to remain airborne.
--You must have a GPS receiver with a suitable data base.

You will need to fly a modified airport pattern much as you would in VFR conditions. Try this lesson in VFR conditions around a seldom used airport until you perfect the procedure. GPS locates an airport by a reference point called the ARP. This point is usually near the center of the airport itself. You want to remain relatively close to the airport. You intercept a direction to the ARP that is 90 degrees to the longest runway. Since you want to be about 1/2 mile from the runway on
your abeam the numbers downwind you will anticipate your turn to downwind by turning when .3 from the ARP (Airport Reference Point). A standard rate turn should position you about 1/2 from the runway on a parallel track. Turn base at 1
mile from the ARP and make an early turn to final to a heading that will allow a 30 degree intercept to the bearing to the ARP. The descent throughout the procedure should be from pattern altitude and at approach speed before turning base.
A normal descent should place you over the runway with some excess altitude as a safety margin. Never accept an ATC
final approach speed higher than your flap or gear speed.

GPS as an Emergency Wing Leveler
Recently an airline captain said that you could use the GPS as a wing leveler. Well, I had a IFR victim taking the long IFR x-country so I used a 60 mile stretch to see if my student could make this GPS method work.

Student made it work but it took several different GPS modes to find the one that seemed to work best. The mode that worked best was the one that displayed course and track one above the other. I covered up the attitude indicator, heading indicator, turn coordinator, and compass. All she had was the sun's shadow and the GPS.

Several things must be pre-planned. You must select a GPS destination that would take you to the nearest VFR. You must
get the aircraft tracking fairly close to the desired track. With practice you can learn to keep the course aligned with the
track. A moments inattention and you will need to S-turn through several courses before getting a match with the desired
track. I do believe the 60 miles that she flew using only the GP"S proved to her that the GPS could well serve as a last-
resort backup perhaps even better than the compass alone.

The GPS for a low weather approach is easy to fly. The GPS approach is more precise than any but the ILS approach.
Why is the FAA still installing localizers? The GPS can serve as a sole system for instrument approaches but it cannot give
the vertical accuracy of an ILS glideslope.

GPS as a substitute
--Locate DME fix
--Fly a DME arc
--Fly to/from NDB
--Locate NDB cross-bearing
--Hold at NDB

Emergency ADF use:
If you lose your AI, HI, etc. and need to fly a particular heading, you can use the ADF as a very useful and reliable aid. Tune to the most powerful station available. With that as a guide you will be able to fly straight and make turns by the required number of degrees.

Visual Procedures
A visual approach allows an aircraft on an IFR flight plan to fly in VFR conditions under ATC control to an airport. Clearance requires VFR conditions at airport and enroute, airport in sight and any traffic in sight.

Visual approaches are not an instrument approach, rather they are an IFR procedure giving means for avoiding a full IP during good conditions that avoids cancellation of your IFR plan. Local weather of VFR minimums is required. The pilot is responsible for all obstacle clearance and has given up the right for a missed approach and going IFR again. Recommended altitudes are mandatory as is the recommended flight track. Part 91 visibility have never been defined. You are protected from IFR planes you do not admit seeing. Visual approaches greatly increase the PIC responsibility of the pilot.

You are not on an instrument approach procedure even though you are adhering to instrument flight rules. If there is any doubt as to the success of a visual procedure, you should remain IFR. Both visual and contact approaches must be flown in VMC. A visual approach can be flown to any airport if ceiling and visibility are above minimums of 500' above minimum vectoring which is always at least 1500 AGL. Though similar, the visual and contact approach are not interchangeable.

Either ATC or pilot can initiate visual approach when you can tell ATC you have the airport in sight or if you have preceding traffic in sight and will maintain separation and wake avoidance. If you see the airport but not the traffic ATC must provide separation. Radar service is terminated when you change to tower frequency. The visual approach clearance does not include missed approach instructions. Missed approaches are handled as a go-around.

A visual approach requires a 1000’ ceiling and 3-mile visibility. What you do visually depends on the ATC clearance. If you are cleared for a named and charted visual approach, you must fly the charted procedure. If your clearance is not named and charted you can fly VFR to get where you are going.

To conduct a visual approach you must be on an IFR flight plan and have airport or traffic in sight with weather at least 1000 and 3. ATC can give clearance at an airport without reported weather if 1000 and 3 is expected. Visual approaches are allowed even if vectoring weather minima do not exist as long as 1000 and 3 do exist. If there is no weather observer the radar controller must be told that you are VFR before he can give you a visual approach. Once you have accepted a visual approach, you are responsible for all traffic separation.

Imagine that the airport/approach is a beautiful woman. You can have visual any time you want, but you've got to request contact.

Visual approach
--ATC or pilot initiation
--Ceiling 1500' or better or pilot must be able to maintain VFR.
--Pilot maintains separation and wake avoidance

Can be offered by ATC or asked for by pilot if ceiling is 1000’ and visibility 3 miles. You must remain clear of clouds. You must have any preceding traffic or the airport in sight. Traffic and wake avoidance is up to the pilot.

On top conditions may be difficult in convective conditions. Clouds often rise at 3000 fpm. Let ATC know so you can file IFR. Ask for an alternate IFR clearance in case of communications failure. You must see and avoid all other traffic but also report all altitude changes as though IFR.

If you are dealing with IFR as a process within a complex maze of strict, unwavering rules requiring passive compliance, they you don’t know how to use and fly the system. there are a number of time and fuel saving ways of using the system to your advantage.

Contact Approach
An IFR pilot can shift responsibility, control and liability out of the hands of ATC by requesting a contact approach. This
allows deviation from published procedures and allows flight to the airport where visibility is reported to be at least one
mile. The pilot must maintain ground contact, remain clear of clouds and provide obstacle clearance. Only you, the pilot,
can do this; ATC cannot. The contact approach has the pilot responsible for terrain clearance, clear of clouds and flight
visibility. ATC must have a procedure (including the published misssed) available should IMC flight be required by the
pilot unable to maintain the contact approach.

Don’t descend until in position to land. Obey minimum safe altitudes and obstruction clearance features. This is a form of scud-running that is safe only if you are familiar with the area. Don’t ask for a contact approach unless you really know where you are and will be all the time. You must have one mile visibility and fly clear of clouds as though SVFR. One mile visibility can suddenly go lower. Don’t hesitate to contact ATC and get an approach clearance. ATC will provide separation only from other IFR traffic and SVFR traffic. The contact approach is a substitute for an IFR approach.

Must be pilot requested and ATC approved. Only airports with IAPs and weather reporting. Cannot be used to reach other airports. Pilot is responsible for obstacles and radar service ends with frequency change.

--The contact approach can only be asked for by the pilot.
--Minimum conditions are 1 mile visibility and clear of clouds.
--ATC does not like the contact approach since its safety is directly related to how familiar the pilot is with the area.
--ATC will never clear a contact approach aircraft below the local minimum safe altitude.
--Requested by pilot
--Clear of clouds and
--1 mile visibility
--Pilot responsible for obstacle clearance

ATC and Visual Approaches
--Determines airport visibility
--Gives alternate (missed) instructions
--Provides separation until handed off to tower

Comparison
Contact Approach ......................................................Visual Approach
--Only pilot initiated ......................................................Pilot or ATC initiated
--Airport required to have instrument procedure charts ..Vectors possible
--Clearance must include missed
Basic VFR minimums exist and can be maintained
approach instructions
--ATC has 1 mile at airport
--ATC radar separation

Weather minimums
SVFR minimums for pilot and ATC ................................1500' and 3 miles

Pilot responsibility
Pilot obstacle clearance .................................................Maintain basic VFR when cleared to follow

Advantages
Enables file IFR to airport without weather reporting.
Area weather must forecast VFR. (New night VFR)

Limitations
Only at airport with instrument procedure ........................Clearance limit to nearby intersection
Airport reporting statute mile ground visibility.
Not to be used to transition to another airport.

The release of an aircraft to tower frequency ends radar service. There have been many instances where the has been verbal confusion between the pilot and ATC. ATC asks you to have runway in sight, you respond with,
"airport in sight". there is a difference and the difference has resulted in many wrong-runway landings as well as wrong airport landings. Additionally ATC records show that pilots are often mistaken when reporting, "Have traffic".

Types of Vectors
--Long-range provided by center
--Short-range into a instrument approach procedure.
--Delay or spacing vectors for traffic separation
--Re-route as a short-cut
--Shortcut to IAP segment not final approach. Limited radar coverage you are required to make any procedure turn. 91.175(j) Usually safer to fly the full approach.
--Weather avoidance requests by pilot and his responsibility.
--Departure during climb but below MVA. Only on IFR departure or on missed. May be above MVA or MIA
--To final so no published course reversal required. 20-30-degree intercept angle. Don’t turn on to final without ATC approval.

Pilots Responsibility Using Vectors: AIM 5-5-6
--Prompt compliance with headings and altitudes
--Challenge any perception of incorrect headings or altitudes.
--Advises ATC if a vector would cause FAR violation
--Terrain and traffic are pilot’s responsibility.

ATC Responsibility Giving Vectors
--For separation
--For noise abatement
--For convenience
--When pilot requests
--IFR planes at or above MVAs
--VFR planes at any altitude or as assigned. "Maintain VFR, separation not provided."

Approach by Vectors
Use P-position
T-turn
A-altitude
C-clearance
Do not repeat everything. ...cleared for approach is enough.

--ATC position given is only informational and need not be repeated.
--ATC turn heading is advisory and need not be repeated or even followed if pilot judgment suggest a better alternative.
--ATC altitude is usually present altitude which need not be repeated. An altitude restriction should be repeated.
--ATC reporting requirement should be acknowledged.

--Duty of pilot is to fly approach and acknowledge the clearance with any restrictions or requirements given by ATC.
--Clearance usually gives a fix, crossing altitude, and approach clearance.
--Acknowledge only that you have the clearance, only if you are familiar with the fix, altitude, and approach.
--Approaches can only be entered via radar vectors or by use of a procedure.
--Course reversals can be made by a procedure turn or by a holding pattern. Sometimes both occur on the same plate.
--Only by reading the plate carefully can you determine if the hold is also a course reversal procedure. A plan view in bold
line tells you yes.
--Advise ATC that you will descend in the hold to allow reasonable descent on leaving the hold. Extension of the hold is
limited to one minute but this can be done at 200 knots.
--When ATC tells you to hold at a five-letter fix, to hold in a cardinal direction, or to hold on a radial, draw the hold and then decide how you are going to turn around. Fly through the fix in every case and then take your pick. You can always turn outbound and make a course reversal. Asking ATC for a helping vector will not work on a checkride.
--Do not expect to be able to fly a holding arrival if you have not configured before your arrival and reduced the potential for distractions. Don’t fly instruments unless you are proficient and current. Get all the ATC help you can but remember that only you can make the decisions.

Charted Flight Visual Procedures (CFVP)
Charted flight visual procedures are used for noise abatement in radar/VFR situations. original intent was to speed up arrivals. It is not an instrument nor a visual approach and does not have a missed approach segment. Not to be logged as an approach. Missed approaches are VFR go-arounds. Determining factor is visibility

Pilot responsibilities
--Acceptance of visual clearance makes pilot responsible.
--Acknowledgment of traffic makes pilot responsible for separation and turbulence avoidance.
--If unable to land you must remain VFR until obtaining additional clearance.
--Must advise ATC if unable to follow

ATC responsibilities
--ATC will clear when pilot has airport or aircraft to follow in sight.
--Minimums are 1500' and three miles visibility with the ceiling 500' above minimum vectoring altitude (1500')
--Radar service canceled when you change to tower(advisory) frequency

PAR f(GCA ground Controlled Approach) Approach (Exists at Lemoore NAS)
This approach is a highly-skilled, labor intensive system being shut down by the military. It provides glideslope and azimuth direction where all turns and descents are at the direction of the radar controller.
On being given the instruction:
"All turns will be standard rate until established on the final approach. Then they will be made half-standard rate. If radio contact is lost for more than seconds, contact tower on (frequency) and execute the prescribed missed-approach procedure."

Every few seconds or so the final controller will issue course and glidepath corrections leading to the runway threshold. I was talked down to within 10 feet of the runway at Travis on a PAR twenty years ago. Great feeling. Once on the ground you may need taxi assistance.

On such approaches the controller would need to know when you had acquired visual references such as lights so that you could be cleared to land visually or to execute the missed approach.

Been There; Done That
Instructor wanted to expose student to a radar surveillance approach or a no-gyro approach. Surprise we were offered and accepted at GCA approach. I thought that the very labor intensive GCA's had been dropped by the military. No radar approaches are presently available in the S.F. Bay Area. The GCA (Ground Controlled Approach)gives you ILS precision without any needles to track. The first controller gets you lined up on the runway and at a selected altitude. The final controller just gives you headings to fly and advice as to how you are doing on the glide slope. They can bring you right down to the runway.

I did this on this long cross country because it is along a route that my student expects to be flying in the future. She also expects to visit the base in the near future to see friends. I instructed her to to visit the GCA facility. Anyone who can establish a fixed rate of descent and hold a heading should be able to fly a survivable GCA procedure.

Airport Surveillance Radar Approach (ASR)
This approach has replaced the PAR in most places with radar. Controllers are requires to practice these approaches and may be more than willing to give you a practice approach. The procedure requires that the airport have the required radar capable of giving heading information. ASR altitudes are recommended only. On final you will be given range to airport and stepdown altitude recommendations for each mile. Altitudes will be higher than for standard instrument approaches.

No-Gyro Approach
#1 Cover up the heading indicator.
#2 Keep aircraft under control.
#3 Do what you are told to do when you are told to do it.

When it is a dark and stormy night and the gyros quit the controller can give you assistance by means of the turn coordinator. He will tell you to turn at standard or half-rate turns to the right or left and tell you when to stop turn. An ASR approach requires that the radar range be reduced which effectively blows-up the picture size for the controller. Usually an entire scope and controller is dedicated for an ASR approach. There will be no handoff to the tower. The radar controller handles the landing clearance, rollout, and advises when to contact ground. A missed approach will continue with the radar advisories.

Visual Descent Points
The non-precision approach contains a death warrant for those who cannot get the approach elements (ducks) in a row. First, is flying the final approach course; second, comes doing it in IMC or at night; third, is a visual illusion; and fourth is getting a visual descent point (VDP). The non-precision approach usually has a minimum of one-mile visibility. Localizers have 3/4 mile and with lights it gets down to 1/2 mile.

Proceeding to the threshold at MDA means that you must dive to reach the thousand-foot markers. This means you will arrive at the runway too fast for a normal landing. The solution is to figure a VDP and use it by timing. Descend from the VDP with proper flaps and power configuration for landing only when you see the runway environment. Personally I use the VDP as a marker for turning downwind during circle-to-land procedures.

The easiest way to get a quick visual descent point is to use the MDA number and use the two left digits as the number of seconds to take off the approach time. Example: Approach time 2 minutes 16 seconds. Approach MDA 420 feet. Take 45 seconds (close enough) off leaves one and on-half minutes for reaching the VDP.

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